2017-2018 Regular Season Predictions

I simulated the 2017-2018 NHL seasons a hundred thousand times to estimate what is likely to
happen. First, I simulated each game ten thousand times using Edgar,
my predictive model for single games. Briefly, I consider shot generation, shot suppression,
shooting and goaltending results, which players are more likely to take the shots that are
taken, special teams, penalties drawn and taken, rest, and home
ice advantage. Injuries, suspensions, and all off-season moves are included.

Although the single-game model is new, the overall method I used is strongly similar to the
one I used last year, with some key
improvements; some of the explanation is copied from last year's preview. I especially thank
Hannah Stuart for estimates for several
prospects (namely, Barzal, Boeser, Chabot, DeBrincat, Fischer, Hischier, Jost, Keller, McAvoy,
Milano, Patrick, Sergachev, Strome, and White) who are likely to play substantial minutes this
year; her estimates of their performances are doubtless much better than mine would have been.

Eastern Conference Point Totals

Team

Mean points

Standard Deviation

Penguins

97.7

8.4

Capitals

96.1

8.5

Blue Jackets

93.1

8.5

Rangers

92.9

8.5

Flyers

92.2

8.5

Canadiens

91.6

8.5

Islanders

91.5

8.5

Maple Leafs

90.5

8.5

Hurricanes

89.1

8.6

Red Wings

89.0

8.5

Lightning

89.0

8.5

Senators

88.3

8.6

Bruins

87.5

8.5

Panthers

86.8

8.5

Sabres

83.0

8.6

Devils

82.3

8.6

Each team's bar is centred on the average point total obtained in the simulations for each team,
sorted with the highest averages to the right, with the divisions indicated by colour.
The changing colour intensities indicate "stanines", that is, each coloured square shows half
of one standard deviation.

Thus, for instance, there is a 20% chance that Toronto finishes with between 88.4 and 92.7 points;
the two adjacent boxes each represent a chance 17%, the next two 12% each, the next two 7% each, and the
extreme pair 4% each. The darknesses of the boxes are chosen to reflect these probabilities.

In total, I expect around six of the teams to finish in the darkest box, around ten to fall into
the adjacent boxes, around seven to fall into the next pair of boxes, around four into the next
pair, and one or two teams to fall into the faintest boxes or beyond. These one or two teams,
which I make no attempt to predict ahead of time, will be much discussed. The proximate cause of their success
or failure will doubtless be a superhuman goaltending performance,
or a horrific cavalcade of injuries, or an exuberance of last-minute
goals and hot shooting. Part of why I make predictive models is that
I enjoy knowing just how unlikely are the various unlikely things that happen every year.

In the east this season, the enormous imbalance of strength between the two divisions will
be a persistent storyline, almost certainly the "third atlantic" seed will be a team outside of
the conference's best eight, to the vexation of purists. It is similarly likely that the
Atlantic division winner may get two rounds of home-ice advantage despite finishing in the bottom
half of the conference.

Playoff cutoffs: 92.3 in the Metropolitan, 89.7 in the Atlantic. The Metro is the hardest
division to qualify from this season.
(These are calculated according to this article.)

Western Conference Point Totals

Team

Mean points

Standard Deviation

Sharks

97.1

8.4

Stars

90.4

8.5

Ducks

90.2

8.5

Blues

89.9

8.5

Kings

89.7

8.5

Wild

89.0

8.5

Flames

88.6

8.5

Oilers

88.4

8.6

Chicago

88.3

8.5

Predators

88.1

8.6

Coyotes

88.1

8.6

Jets

88.0

8.5

Canucks

85.5

8.6

Knights

81.8

8.6

Avalanche

81.8

8.6

The west is full of gridlock, as is typical of the NHL today, but with a handful of clear
distinctions. The Sharks benefit from a strong all-around team with no substantial weaknesses
and a very generous schedule, playing two of the weakest teams in the conference many times.
Vancouver should have an especially frustrating year, being nowhere close to the playoffs but also
somewhat insulated from the very bottom of the barrel where the best draft picks marinate. The
remaining teams I expect will cluster tightly for most of the year.

Playoff cutoffs: 89.0 in the Pacific, 88.3 in the Central. The Central is the easiest division
this season, a big drop in overall strength from last season.

Divisional Breakdowns

Atlantic Division

Team

Playoff Chance

Canadiens

59%

Maple Leafs

54%

Red Wings

47%

Lightning

47%

Senators

44%

Bruins

40%

Panthers

37%

Sabres

21%

The most average of the divisions, the Atlantic is the trickiest to distinguish between teams.
Most teams have low probabilities, suppressed by having to play Metro teams constantly. Montreal's
defence remains very strong though their offence is weak; Toronto's offence (at 5v5 but
especially on the power-play) remains strong though their defence is weak; they are likely to fight
for the division which should please hidebound traditionalists and tv networks. The Sabres are
improved but remain in the bottom of the division; many of their hopes to escape rely on a new
coach whose impact is not considered by Edgar. Ottawa were extremely fortunate last year (that's
part of why their run to within a goal of the Stanley Cup Finals was such good theatre)
and are likely to regress severely but still remain near the playoff bubble where they have been
for most of recent memory. Somewhat more surprising to me is Detroit also in this bubble; their
5v5 play is ordinary but their penalty differential and their special teams results should keep
them in playoff races.

Metropolitan Division

Team

Playoff Chance

Penguins

80%

Capitals

74%

Blue Jackets

61%

Rangers

60%

Flyers

57%

Islanders

54%

Hurricanes

42%

Devils

15%

The Devils are improved somewhat from last season (especially by the addition of Nico Hischier) but
the division improved around them just as much, leaving them chained to the basement, Carolina is in
a similar but not-quite-as-dire spot. The Capitals are weakened but still very strong, whereas
Pittsburgh is not obviously weaker from the team which won the cup last year. The Rangers replacing
Girardi with Shattenkirk have upgraded substantially and young Columbus players should have no
trouble replicating much of last years success though Bobrovsky is expected to regress somewhat.
Some will be surprised by Philadelphia's relatively high position, but their special teams rates
are expected to be near-league best and the addition of Nolan Patrick will help at 5v5 considerably.

Central Division

Team

Playoff Chance

Stars

64%

Blues

62%

Wild

58%

Chicago

54%

Predators

54%

Jets

53%

Avalanche

25%

Colorado were very unlucky last season in addition to also being very weak and while their luck will
surely improve the overall skill of the team is more or less unchanged. On the other hand, serious
injuries and adding weak players who are likely to get lots of minutes drags Nashville back into the
back. Winnipeg are hampered by weak expected special teams play, but nevertheless have a better-than
50% chance of making the playoffs, largely because of the lack of any very strong teams and also the
profileration of weak Pacific teams.

Pacific Division

Team

Playoff Chance

Sharks

86%

Ducks

61%

Kings

58%

Flames

53%

Oilers

52%

Coyotes

51%

Canucks

38%

Knights

23%

The Golden Knights could easily have been in the thick of things had they expansion drafted for
immediate impact, but instead they chose to make many deals for picks and obtained the predictably
weak roster they will ice for much of the season. Even with very generous assumptions for
Shipachyov, I still expect them to be league-worst in overall goal rates, overall penalty
differential, and overall special teams performance, dramatically so in the last case. Vancouver
will also be notably weak, in a humdrum sort of way. Taking advantage of many favourable matchups
(especially with VGK and VAN), I expect the Sharks to handily take the division. The remaining
teams are very tightly bunched; the Kings remain in the pack with their extremely strong defence,
the Coyotes are much-improved in the off-season.

Stat Breakdowns

Considering all situations, there is one obvious "top" tier: Pittsburgh, primarily offensive,
and San Jose, primarily defensive. Washington are slightly behind and more balanced. As always
there is substantial clumping in the middle, but several pairs of teams make for stark contrasts;
most obviously, Toronto and Montreal arrive at similar just-above-50% goal shares through very
different approaches. The four weakest teams have similar goal differences but also show a variation
of style. For an expansion team, which is for that reason expected to lose early and often, a bias
towards more goals for both teams (that is, towards the quadrant marked "FUN") is probably no bad thing.

Special teams are rightly subordinated to even-strength play in analytics, but they still comprise
around a fifth of the icetime and a fourth of the goals in the sport, on average, so penalty
rates will have a substantial impact on a season's results. Vancouver and Buffalo are expected to take
very few penalties (preferring to lose at 5v5) and Vegas is expected to take the most in the league.
Dallas has many players who take and draw many non-offsetting minors, so they are expected to spend a
lot of time on special teams, this is a wise strategy for them since their special teams play is
generally strong (see next chart).

On special teams themselves, only a handful of teams stand out. In a good way, the Penguins and
Flyers seem especially strong, most notably while short-handed. The very dangerous Toronto
power-play will likely make some teams change their game plans specifically to try to avoid taking
penalties. Winnipeg are likely to be sunk again by their poor penalty-killing, and the Knights'
weakness will show very markedly on special teams.

(Montreal and Los Angeles are right on top of one another at around (0.18,0.195), similarly
St Louis and Calgary are together near (0.19,0.195).)

Rest

Not all teams are equally affected by rest. It's commonplace to highlight games where one
team is playing tired (that is, after playing the night before) and the other team is not. However,
in the past substantial deviations from typical home win percentages are seen only when the team
playing at rest disadvantage is the home team---tired road teams don't seem to be seriously affected.
When we restrict our attention to these games, we see that the variation of rest-affected games
is not very large. Benefits are not confined to teams in a particular area of the continent.
The starkest bit of scheduling is Carolina, who must play at home while tired (essentially,
giving home ice advantage to their opponent) seven times while only receiving a matching
benefit in another game three times. They play, in essence, 37 home games and 45 road games.

Wooden Spoon

Since the league hasn't yet implemented Gold drafting, many teams will once again play many
games at the end of the year which they would rather lose. Although there will be many trades
and confusions between now and the end of the year, these are the early probabilities (including
all three lotteries) for who will get the 2017 first overall draft pick.

Team(s)

Chance of First overall pick

CGY

No Pick

S.J,PIT,WSH

1%

CBJ,NYR,PHI,MTL

2%

DAL,ANA,TOR,STL,L.A,MIN,DET,T.B,CAR,CHI,EDM

3%

NSH,WPG,ARI,OTT,BOS,FLA

4%

VAN

5%

NYI (via CGY)

6%

BUF,N.J

7%

COL,VGK

8%

Weaknesses

The general weaknesses of Edgar are discussed at the end of the model description here but I outline here how those weaknesses may be relevant to this season.
Roughly speaking, I give my own opinions here about where I feel the Edgar predictions may be
wrong. Of course, I do not modify them in any way, that would be dishonest. As always, I
strive for the best model (that is, balancing according to my professional judgment accuracy,
interpretability, parsimoniousness, and efficiency), not seeking to be an oracle.

One weakness is the lack of coaching effects; it's natural for fans to expect that a new coach
will be better than the previous one (after all, he is so easily blameable for the previous
weaknesses, though they may not have been more than vaguely his fault) but of course the new coach
may well be worse. In this case I expect that the change in Buffalo should improve their results
by a few points. None of the other coaching changes strike me as especially substantial.

More substantial weaknesses in Edgar are the lack of accounting for age and and for quality of
teammates inflating or deflating results. These weaknesses are most salient when they are combined;
that is, when a team has very important players (with many minutes, playing with many other players)
who are strongly affected by age (or leave the team entirely). Specifically, I worry this year
that Joe Thornton's past two years of results may badly represent his output in this coming
season, and San Jose will perhaps not be as clearly above the other Western conference teams as they
appear.

Similarly, although not as focussed on a single player, I am concerned that Edgar's lack of age
consideration will exaggerate Detroit's abilities, since many of Detroit's high-minute players are
fairly old (in hockey terms).